Coming to an end with its 15th season in Spring 2020, Criminal Minds has been one of the longest-running dramas on television. Throughout its run of over 300 episodes, the team has seen many disturbed and terrifying suspects. These bad guys are so twisted, it's enough to give anyone nightmares, including the Behavioral Analysis Unit (BAU) team members themselves.

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Some suspects were caught and never heard from again, while others got away and came back to haunt the BAU. With such compelling characters, it's easy to see why the show lasted all these years. Here are the 10 most twisted suspects on Criminal Minds.

Scratch

In the episode "Mr. Scratch" the team is dealing with three separate murderers from across the country. Two of the suspects don't recall killing anyone. They only remember a distinct smell and getting attacked by "a shadow monster with talons." When a fourth case with the same clues comes up, the BAU investigates to find a man going by the name Scratch has hypnotized them into committing such horrifying acts. A criminal mastermind who plants false memories and makes his victims take the lives of loved ones is a chilling villain indeed.

Frank Breitkopf

The BAU makes a deal with the devil when they first encounter Frank. He is first seen holding a school bus full of children hostage. To save the kids, the BAU lets him escape with Jane, the love of his life, and the woman he vows can keep him from killing again. When Jane leaves to find Gideon, Frank goes on the hunt again, this time taking Gideon's friend Sarah as vengeance. Sarah is found dead in Gideon's apartment, and it's clear Frank has set up the BAU agent.

The Womb Raider

Thomas Yates, a.k.a. The Womb Raider first appeared in season seven through flashbacks. The BAU's memories of the case though are shocking, as the episode reveals a misogynist, demented serial killer who stabbed women to death and removed their reproductive organs.

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Later he started removing their vocal cords after they had died. Yates tormented the BAU by making a deal to avoid death row in exchange for the revelation of one of his 101 victims each year. He returns in season 12, attempting to reform after escaping prison, but succumbing to his murderous needs again.

Roger and Anita Roycewood

This couple looks like a happily-married pair on the outside, but underneath lies a sinister shared secret: they are child abductors. One of their earliest victims was a boy named Charlie who grew into a teenager as their prisoner. They used Charlie to lure and trap other kids in their dark and twisted web. The couple also owned a funeral home with a crematorium. The Roycewoods burned misbehaving and uncooperative children. To abduct so many kids and use one of their victims to help with their dirty work shows they didn't have a strong parental instinct.

Dr. Mason Turner

The not-so-good doctor used his brother Lucas to collect homeless people for his sick work. Mason was bedridden and needed Lucas to bring him victims for his experiments to find a fix for his predicament. Lucas, unfortunately, didn't understand what he was doing as wrong, due to his intellectual disability.

As each victim is killed, Mason had Lucas get rid of the bodies by feeding them to the pigs on their farm. Apparently, Dr. Turner forgot the number one rule of the Hippocratic Oath: Do no harm. It's a story that sounds too farfetched to be real, but Criminal Minds has a way of bringing fiction to life.

Adam Rain

This serial killer is a collector of manmade marionettes, emphasis on the manmade. He tortured his victims with limb contortion and turned them into lifesize puppets on strings. The marionettes were a remnant from his childhood, as his father used to put on shows for him.

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As a boy, he witnessed a masked robber kill his father, and the trauma came back after he suffered a severe car accident as an adult. Adam woke up childlike and murderous, reliving his father's death with his own human puppets.

Jeffrey Charles

When kids go missing in Ozona, Texas and show up dead, the BAU thinks it's the work of the local Boogeyman, a recluse named Joseph Finnegan. Evidence disproves his guilt though, so they move onto the theory that it's another well-known adult in the community that the kids trust. It turns out though, that the kid killer is another kid: Jeffrey Charles. Jeffrey hated that his father, the school counselor, spent so much time with other kids. Eventually, he cracked and started bludgeoning his classmates to get back at his dad.

Floyd Feylinn Ferell

Barbecue restaurant owner Feylinn Ferell has a deeply twisted secret recipe: human bodies. A cannibal who believed he was possessed by a demon that demanded he feast on flesh, he was institutionalized as a child. During his time at the asylum, he studied Satanism. Once released at 18-years-old, he opened his barbecue restaurant and began claiming victims. But practicing cannibalism himself wasn't enough. Before killing his victims, he made them eat the fingers of his other victims first. Floyd left just enough of his victims to carve Satanic symbols into their torsos.

Carl Buford

Derek Morgan aiming a gun in Criminal Minds.

Thought to have been a positive force from Morgan's past, Buford turned out to be a pedophile turned serial killer. Morgan himself was a victim of the man's vile actions, but after losing his father at such a young age, Buford became a paternal figure to the troubled youth. The memories of Buford's betrayal became hidden in Morgan's past until they resurfaced when he was accused of being a serial killer. Buford is one of the worst kinds of criminals, as he tries to convince Morgan that he never hurt the boy and that Morgan could have said no.

The Romani Family

The Romani family, part of an ethnic group formerly called gypsies, lives up to the worst traits associated with that community. A mother, father and son break into a family's home, kill the parents and take the daughter. They are grooming the boy to become a killer. Worse still, this pattern of murders and abductions goes as far back as 1909 but was never caught because they were so spread apart. This generation of the Romani family isn't the first to engage in serial abduction and killing. It's their tradition.

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